1. Field of the Invention
The present invention relates to a hinge, especially to a hinge with an oil-retaining collar mounted around the positioning spacers and washers filled with lubricating oil.
2. Description of the Prior Arts
Electronic devices such as laptops, mobile phones, personal digital assistants (PDA), etc. have a base, a cover and a hinge. The hinge connects the cover to the base to allow the cover to pivot relative to the base.
The conventional hinge has a rotating bracket, a shaft, multiple washers, a stationary bracket, a stationary positioning spacer, a rotating positioning spacer, a biasing member and a nut. The rotating bracket connects to the cover of the electronic device and is mounted on an end of the shaft. The stationary bracket, the washers, the stationary positioning spacer, the rotating positioning spacer and the biasing member are mounted around the shaft. The nut is mounted securely on another end of the shaft to hold the all components. The stationary bracket connects to the base of the electronic device. The stationary positioning spacer has two detents. The rotating positioning spacer has two bosses corresponding to the detents of the stationary positioning spacer to hold the rotating positioning spacer in place.
The washers and the positioning spacers are respectively mounted and abut the rotating and stationary brackets to provide a resistance force so that the cover can be reliably positioned at a desired height. The washers and the positioning spacers further have holes or recesses filled with lubricating oil to prevent those components from wearing away and to keep the pivotal hinge rotating smoothly. However, lubricating oil might flow out of the pivotal hinge between the washers and the positioning spacers causing the pivotal hinge to rotate roughly and wear away if not filled with enough lubricating oil.
To overcome the shortcomings, the present invention provides a pivotal hinge with an oil-retaining collar to mitigate or obviate the aforementioned problems.